So as a post-mortem of sorts, what possessed you to upgrade the OS installed Perl? It seems like a blind spot that even veteran system engineers and system administrators fall pray to, so I'm always a bit curious when things like this happen.

FWIW, as a general rule it's best to leave what the OS ships with alone as much as possible. Sorry you had to find that out the hard way. :/

You're just some end user that doesn't understand security by any shape or means right? Not someone that runs something high profile... This is the exact crap that the high level companies getting hacked seem to run by, then wonder why people are slightly annoyed when they lose 70million customer details rfom their db including unsalted passwords and credit card details...

Nonsense -- when you upgrade, be ready to roll back any updates that break your stuff -- or be ready to fix your broken stuff -- if you're not ready for rollback or fixing, then an upgrade doesn't get you anything